Temperature control system



Feb. 17, 1948. I. E. WIEGERS 2,436,275

TEMPERATURE CONTROL SYSTEM Filed July 22, 1943 IN VEN TOR Patente d Feb. 17.

mums-common srsmu Irvin E. Wlercrs. Overland, Mo. Application July 22. ms. Serial No. 495.864

80lalms. (cits-"2r This invention relates to a semi-automatic system of temperature control in which manual operation is combined with automatic operation.

It is the object of the invention to provide a control system which requires no external source of power other than that provided by manual effort and which can be successfully installed by a layman or semi-skilled worker. Another object is to provide thermostatic control low in initial cost and tending to produce economical operation of the heating or cooling unit.

response of the thermostatic means. and makes the action more positive. Thermostat parts are mountedon frame 38. when the temperature at the thermostat falls below the point for which it is set, the thermostat may be reset'by raising hook lever 82 to such an extent that cam 33 causes pawl 23 to deflect snap disc 30 to its upwardly concave position. By this The accompanying drawing illustrates such a mechanism applied to an ordinary domestic heat ing furnace.

Figure 1 shows a ossible draft ment on such a furnace.

Figure 2 shows a thermostat foruse with this control system. a

The thermostatshown in Figure 2 is preferably installed in the living quarters heated by the furnace in Figure l. The system illustrated is so arranged that when the temperature at the thermostat reaches the point for which it is set. the rate of combustion in the furnace is retarded by the draft controls.

control arrange.

Figure 1 shows a furnace 3. having a firing door 4, ash removal door 5 with a draft regulator-8,

interconnected with flue damper ill in flue ii by means of cable I, i2, i3, which passes through pulleys 8 and It. Blasing weight 8 is attached to cable 7. Also interconnected at point I5 is the cable It passing over pulley i! to thermostat in Figure 2 by means of cable I 8. In Figure 2 cable I8 is secured to open-link chain is which is suspended from hook 28. Hook 2b is pivoted on shoulder screw 2i and is held in place by latch 22 engaging pawl 23 which is pivoted on shoulder screw 26.

Yoke 25 is made of material having a smaller coefficient of expansion than thatof column 26 which is restrained by adjusting screw 21, operated by calibrated knob 28. The force due to the unequal expansion" of yoke 25 and column 26 is transmitted to thrust disc 29 causing snap disc at to reverse its concavity when temperature reaches point for which thermostat is set. Snap disc 30 strikes pawl 23 unlatchlng hook 211 which disengages chain l9 causing draft regulator 5' to close and biasing weight 8 to open damper Hi to the extent permitted by the slack in chain l9 at section 3|. combustion ratein furnace 3.

The use of a snap acting member prevents fric-- tion in the latch members or variations in the biasing weight from aflecting the temperature This action tends to retard means the efl'ect known as "diil'erentiaP due to snap actionis eliminated. I Pawl 23 which is weighted by mass 35 will then engage latch 22. The chain i9 can be used to manually raise the biasing weight 8 and the draft restored to position for increased combustion by engaging chain l9'on hook 20.

The combustion retarding or accelerating action or the control system may be varied by changing the points at which thechainE i8 is engaged with the operating hook 2d and the stationary'hook 3 1. I prefer to apply this control system to a heating furnace in such a manner that the rate of combustion is automatically retarded since this makes for maximum economy of fuel but a system can be readily made in such a manner as to increase the rate of combustion automatically. In such a last-named system the coefllcient of. expansion of the material of column 26 would be less than the coefllcient of expansion of the material of yoke 25; the biasing weight 8 would be removed from the cable i and applied on the cable l3 and the cable It would act in a direction opposite from that shown in Figure 1. There are other uses and applications ofthis invention which is limited only by the claims.

The fact that manual operation is required is an advantage in a hand fired furnace since it serves as a reminder of the fuel requirements of the furnace and also roughly indicates the rate of combustion.

What I claim as my invention-is: a

1. A temperature responsive device comprising:

temperature responsive means,.manually operated means, snap acting means moving in one direction under the'infiuence of the temperature responsive means and moving in the opposite direction under the influence of the manually operated means, latchmembers arranged to be disengaged by action of the snap acting means moving under the influence of the temperature responsive means.

2. A temperature responsive device comprising: temperatureresponsive means. manually operated means, sna acting means movable in one direction by the manuallyoperaterl meansand movable in the opposite direction by the temperature responsive means, latch members arranged to be disengaged by the snap acting means when moved by the temperature m nlive 'means. I

eponsive means.

IRVIN E. WLEGERS.

some

REFERENCES CITED The following reference: are oi record in the tile oi this patent:

Number 511,283 1,116,534 1,571,270 1,919,264 2,028,363 2,214,875 2,217,419

UNITED S'I'A'I'ES PATENTS Name Date Tatham Dec. 19, 1893 Baker Nov. 10, 1914 Jensen Feb. 2, 1928 Vaughn July 25, 1933- Timm et ai Jan. 21. 1936 Jackson Sept. 10. 1940 Saul Oct. 8, 1940 

